Murray is 8 months, rescue and was neutered about 3 weeks ago.
Before the procedure....
Extremely nippy, major wanderer, insanely food driven-hyper, and overall a very rambunctious pup.
Post procedure (3rd week)
Loves to lounge, as in lay down anywhere in the house and CHILL, as in observe activity around him. Before he would have to say hello, by barking, sniffing, or nipping at your feet no matter what.
Still very eager to chase any type of ball and will chase it vigorously, but the speed and enthusiasm at which he returns has definitively changed, he'll "jog" back - not sprint like his life depended on it.
His protectiveness of me and his immediate surroundings (my workplace and mu house) has increased 5-fold, he is much more territorial and protective and will bark at the sight on any unrecognized person that comes in one of these two places.
Maybe his changes in behavior are merely coincidental and have nothing to do with the operation but I do strongly feel alot of that crazy "Monkey Energy" is out of his system and he's a lot more control of his emotions -- if that makes any sense?
My 2 cents...
Do I have any regrets on the neuter? Not really... but I suppose these is some truth to a male's mojo or lack there of and castration.